THE FLOWERS OF BRAZIL 



red is avoided, being visited only if mingled with a little blue or 

 yellow, as is usually the case. Certain experiments actually seem 

 to prove that insects are "red and green colour-blind" ; that is, that 

 they do not perceive red as contrasting with green. In Europe there 

 are hardly any pure red flowers ; but in Brazil, as we have seen, 

 there are quite a number, and it has been suggested that in South 

 America the red flowers are visited and fertilized by Humming- 

 birds, which are not colour-blind. As far as my own observations go, 

 I cannot flatly assert that all insects are colour-blind, and prefer to 

 wait until the experiments have been extended to include the 

 Brazilian butterflies and hymenoptera, which I have often seen 

 visiting scarlet flowers. In the gardens of Rio, the parks of Nova 

 Friburgo, and the Horta da Luz of Sao Paulo are bushes with green, 

 sharp-cornered leaves, on which, in the month of May, great red 

 stars of such brilliance burst forth that one is literally dazzled by 

 them. Such a star is 12 to 16 inches in diameter; it consists of 

 twenty or more flame-red, narrow, pointed leaves, which surround 

 the actual inconspicuous inflorescence. This bush is a Euphorbia, 

 which the Brazilians call "Papagaio" ; but they give that name to 

 many brightly-coloured flowers. The assumption that insects would 

 be attracted from a distance by these brilliantly luminous flowers 

 was fairly obvious, and I did see whole flocks of butterflies hovering 

 over the bushes; and great numbers of the splendid Brazilian 

 Swallowtail, the black and yellow Thoas, settled on the flowers in 

 order to suck their nectar. In Nova Friburgo an engineer told me 

 that he was colour-blind, and could not distinguish the red of the 

 leaves surrounding the flower: for him they were indistinguish- 

 able from the ordinary leaves. If the butterflies were in the same 

 case, the great attractive power of the "Parrot-flower" was un- 

 intelligible. 



The example of this Euphorbia teaches us, however, something 

 more. It demonstrates the many-sidedness of Nature, who does not 

 by any means rely upon one single scheme, but applies the most 

 various means to attaining one and the same end. As a general thing 

 the visible apparatus which is designed to attract the insects by 

 brilliant colour which contrasts with its surroundings consists of the 

 flower itself — that is, of its petals. In the Parrot-flower, however, 

 the blossoms are small, inconspicuous cups with yellow rims, and 

 the function of display is allotted to leaves with mid-ribs and lateral 

 innervation. But no flower could attract the gaze more forcibly than 

 these rosettes of large red leaves. 



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